ECG in dilated cardiomyopathy: specific findings and long-term prognostic significance

Prevalence and clinical significance of low QRS voltages in healthy individuals, athletes, and patients with cardiomyopathy: implications for sports pre-participation cardiovascular screening

Low QRS voltages (LQRSV), defined as a QRS amplitude from peak to nadir < 0.5 mV in all limb leads, are an emerging diagnostic finding on the electrocardiogram (ECG). In healthy individuals and athletes, LQRSV are rare (2.2-4% of elite athletes, 0.5% of recreational athletes, and 0.3% of sedentary individuals). LQRSV athletes commonly show ventricular arrhythmias (VAs) on exercise, and up to 40% of those with LQRSV and VAs have late gadolinium enhancement (LGE) on cardiac magnetic resonance (CMR). The prevalence of LQRSV in arrhythmogenic cardiomyopathy ranges from 17-40%, predicts left ventricular (LV) involvement, and is correlated with more extensive LGE replacement on CMR. In hypertrophic cardiomyopathy (HCM), LQRSV ranges from 0.7-11%. LQRSV-HCM patients have more segments with LGE, despite relatively smaller LV mass, suggesting a more advanced clinical stage and a worse prognosis. In dilated cardiomyopathy (DCM), LQRSV range from 6-7%, but may be higher (36%) in certain genetic forms of DCM. On a follow-up, LQRSV are independently associated with incident cardiac events, such as sudden death, sustained ventricular arrhythmia, or appropriate internal cardioverter defibrillator discharge. In cardiac amyloid, LQRSV range from 34-66% and demonstrate a negative prognostic value, with worse clinical outcomes regardless of underlying biologic, genetic, and clinical variables. In conclusion, LQRSV deserve careful consideration for exclusion of arrhythmogenic substrates in healthy individuals, athletes, and patients. While additional research is needed, it is reasonable that LQRSV should trigger clinical investigation to exclude underlying diseases at risk of life-threatening arrhythmias.

Fragmented QRS, a strong predictor of mortality and major arrhythmic events in patients with nonischemic cardiomyopathy: A systematic review and meta-analysis

Background and Aims

Fragmented QRS (fQRS), which is associated with rhythm disturbances, can predispose the heart to fatal ventricular arrhythmias. Recently, accumulating studies indicates that fQRS is associated with poor prognosis in various types of cardiomyopathies. Therefore, we assessed the association between fQRS with all-cause mortality and major arrhythmic events (MAEs) in patients with nonischemic cardiomyopathy, in this systematic review and meta-analysis study.

Methods

We performed a comprehensive search in databases of PubMed/Medline, EMBASE, and Web of Science from the beginning to December 31, 2022. Published observational studies (cohorts, case-control, or analytical cross-sectional studies) were included that report the prognostic value of fQRS in patients with different types of nonischemic cardiomyopathies for MAEs (sudden cardiac death, sudden cardiac arrest, sustained ventricular tachycardia [VT], ventricular fibrillation [VF], and appropriate shock) and all-cause mortality. We pooled risk ratios (RRs) through raw data and adjusted hazard ratios (aHRs) using "Comprehensive Meta-Analysis" software, Version 2.0.

Results

Nineteen cohort and three analytical cross-sectional studies were included in this meta-analysis involving a total of 4318 subjects with nonischemic cardiomyopathy (1279 with fQRS and 3039 without fQRS). FQRS was significantly associated with an increased risk of all-cause mortality in patients with nonischemic cardiomyopathy (pooled RR: 1.920; 95% confidence interval [CI]: 1.388-2.656, p < 0.0001/pooled HR: 1.729; 95% CI: 1.327-2.251, p < 0.0001). Also, the risk of developing MAEs in the presence of fQRS was significantly increased (pooled RR: 2.041; 95% CI: 1.644-2.533, p < 0.0001/pooled HR: 3.626; 95% CI: 2.119-6.204, p < 0.0001). In the subgroup analysis, the strongest association between fQRS presence and increased MAEs was observed in patients with hypertrophic cardiomyopathy (HCM) (pooled RR: 3.44; 95% CI: 2.07-5.71, p < 0.0001/pooled HR: 3.21; 95% CI: 2.04-5.06, p < 0.0001).

Conclusion

Fragmented QRS could be a prognostic marker for all-cause mortality and MAEs in patients with various types of nonischemic cardiomyopathies, particularly HCM.

[Acute heart failure with altered ejection fraction : Electrocardiographic signs with mortality at the Abidjan cardiology institute]

INTRODUCTION

Heart failure with impaired ejection fraction (HFIEF) represents the end-stage of most cardiac diseases, and is responsible for a high mortality rate. In order to identify patients at risk, numerous clinical and paraclinical prognostic factors have been proposed. The electrocardiogram (ECG), easy to perform and inexpensive, retains a powerful role in the prognostic evaluation of heart failure patients. The aim was to evaluate ECG signs associated with mortality in a retrospective cohort of patients with ICFEA.

METHODOLOGY

The study was observational and analytical based on retrospective data collected from patients benefiting from a primary hospitalization for ICFEA at the Abidjan Heart Institute from January 2018 to July 2020.

RESULTS

Of the 370 patients included, 197 had died by August 1, 2020, representing an overall mortality of 53%. Mortality progressed gradually up to one year, then remained unchanged up to 30 months. In multivariate Cox regression including ECG variables only, the presence of intra-ventricular conduction disorders (OR: 1.80; 95% CI [1.01-3.25]), microvoltage (OR: 1.82; 95% CI [1.05-16]), and pathological Q waves (OR: 1.70; 95% CI [1.02-2.83]), were significantly associated with overall mortality. When ECG variables and clinical, paraclinical and therapeutic demographic variables were included, only the presence of pathological Q waves (OR:1.74; 95% CI [1.01-3.01]) persisted as a risk factor for mortality. Hypertension and treatment of heart failure, in particular ACEI/ARII, beta-blockers and ARM, were protective factors. The presence of Q waves was associated with a significant reduction in survival, based on curves obtained using the Kaplan-Meier model.

CONCLUSION

ICFEA is responsible for high mortality, mainly in the year following the 1st hospitalization for cardiac decompensation. The presence of pathological Q waves is the only electrocardiographic sign that remains statistically associated with a poor prognosis, after adjustment.

Electrocardiographic abnormalities in patients with cardiomyopathies

Abnormalities in impulse generation and transmission are among the first signs of cardiac remodeling in cardiomyopathies. Accordingly, 12-lead electrocardiogram (ECG) of patients with cardiomyopathies may show multiple abnormalities. Some findings are suggestive of specific disorders, such as the discrepancy between QRS voltages and left ventricular (LV) mass for cardiac amyloidosis or the inverted T waves in the right precordial leads for arrhythmogenic cardiomyopathy. Other findings are less sensitive and/or specific, but may orient toward a specific diagnosis in a patient with a specific phenotype, such as an increased LV wall thickness or a dilated LV. A "cardiomyopathy-oriented" mindset to ECG reading is important to detect the possible signs of an underlying cardiomyopathy and to interpret correctly the meaning of these alterations, which differs in patients with cardiomyopathies or other conditions.

The Diagnostic Value of the 12-Lead ECG in Arrhythmogenic Left Ventricular Cardiomyopathy: Novel ECG Signs

BACKGROUND

Electrocardiographic (ECG) findings in arrhythmogenic left ventricular cardiomyopathy (ALVC) are limited to small case series.

OBJECTIVES

This study aimed to analyze the ECG characteristics of ALVC patients and to correlate ECG with cardiac magnetic resonance and genotype data.

METHODS

We reviewed data of 54 consecutive ALVC patients (32 men, age 39 ± 15 years) and compared them with 84 healthy controls with normal cardiac magnetic resonance.

RESULTS

T-wave inversion was often noted (57.4%), particularly in the inferior and lateral leads. Low QRS voltages in limb leads were observed in 22.2% of patients. The following novel ECG findings were identified: left posterior fascicular block (LPFB) (20.4%), pathological Q waves (33.3%), and a prominent R-wave in V1 with a R/S ratio ≥0.5 (24.1%). The QRS voltages were lower in ALVC compared with controls, particularly in lead I and II. At receiver-operating characteristic analysis, the sum of the R-wave in I to II ≤8 mm (AUC: 0.909; P < 0.0001) and S-wave in V1 plus R-wave in V6 ≤12 mm (AUC: 0.784; P < 0.0001) effectively discriminated ALVC patients from controls. It is noteworthy that 4 of the 8 patients with an apparently normal ECG were recognized by these new signs. Transmural late gadolinium enhancement was associated to LPFB, a R/S ratio ≥0.5 in V1, and inferolateral T-wave inversion, and a ringlike pattern correlated to fragmented QRS, SV1+RV6 ≤12 mm, low QRS voltage, and desmoplakin alterations.

CONCLUSIONS

Pathological Q waves, LPFB, and a prominent R-wave in V1 were common ECG signs in ALVC. An R-wave sum in I to II ≤8 mm and SV1+RV6 ≤12 mm were specific findings for ALVC phenotypes compared with controls.

Electrocardiographic characteristics associated with late gadolinium enhancement and prognostic value in patients with dilated cardiomyopathy

Background

Late gadolinium enhancement (LGE) cardiac magnetic resonance (CMR) imaging has emerged as an important tool for assessment of patients with dilated cardiomyopathy (DCM). Electrocardiography (ECG) is an accessible, reproducible, low-cost diagnostic and prognostic tool. This study aimed to investigate the ECG characteristics associated with LGE, as well as to assess the prognostic significance of ECG in patients with DCM.

Methods

Consecutive patients diagnosed with DCM by CMR [left ventricular ejection fraction (LVEF) < 50%] between 2011 and 2020 were included. Multivariable analysis was conducted to evaluate ECG predictors associated with LGE. Receiver operating characteristic (ROC) analysis was performed to assess the diagnostic performance of ECG in combination of clinical data and LVEF for LGE. Two composite outcomes were also assessed among patients with and without ECG predictors: (1) sudden cardiac death (SCD), sustained ventricular arrhythmia, or appropriate implantable cardioverter-defibrillator (ICD) therapy, and (2) all-cause death or hospitalization for heart failure.

Results

A total of 422 patients, with a mean age of 59.5 ± 16.3 years (58.3% male), were included. LGE was present in 169 (40%) of the patients. Multivariable analysis identified lateral inverted T-waves, intraventricular conduction delay, low voltage, and fragmented QRS as independent predictors of LGE. ROC analysis showed a significant increase in the area under the curve (AUC) when ECG predictors of the four aforementioned characteristics were added to the clinical-LVEF model (AUC 0.66, 95% CI 0.59-0.71 vs. 0.72, 95% CI 0.67-0.78, p = 0.003). During a median follow-up of 2.7 years (IQR 0.8, 5.2), 16 events of SCD, sustained ventricular arrhythmia, or appropriate ICD therapy, and 70 events of all-cause death or hospitalization for heart failure occurred. ECG predictors were independently associated with SCD, sustained ventricular arrhythmia, or appropriate ICD therapy (HR 4.84, 95% CI 1.34-17.40, p = 0.01). However, ECG predictors were not associated with all-cause death or hospitalization for heart failure (HR 1.22, 95% CI 0.76-1.96, p = 0.39).

Conclusion

In patients with DCM, lateral inverted T-waves, intraventricular conduction delay, low voltage, and fragmented QRS were independently associated with LGE. Additionally, these ECG predictors had prognostic value for predicting SCD, sustained ventricular arrhythmia, or appropriate ICD therapy, assisting clinicians in stratifying SCD risk and identifying primary prevention ICD implantation candidates.

The pivotal role of ECG in cardiomyopathies

Cardiomyopathies are a heterogeneous group of pathologies characterized by structural and functional alterations of the heart. Recent technological advances in cardiovascular imaging offer an opportunity for deep phenotypic and etiological definition. Electrocardiogram (ECG) is the first-line diagnostic tool in the evaluation of both asymptomatic and symptomatic individuals. Some electrocardiographic signs are pathognomonic or fall within validated diagnostic criteria of individual cardiomyopathy such as the inverted T waves in right precordial leads (V1-V3) or beyond in individuals with complete pubertal development in the absence of complete right bundle branch block for the diagnosis of arrhythmogenic cardiomyopathy of the right ventricle (ARVC) or the presence of low voltages typically seen in more than 60% of patients with amyloidosis. Most other electrocardiographic findings such as the presence of depolarization changes including QRS fragmentation, the presence of epsilon wave, the presence of reduced or increased voltages as well as alterations in the repolarization phase including the negative T waves in the lateral leads, or the profound inversion of the T waves or downsloping of the ST tract are more non-specific signs which can however raise the clinical suspicion of cardiomyopathy in order to initiate a diagnostic procedure especially using imaging techniques for diagnostic confirmation. Such electrocardiographic alterations not only have a counterpart in imaging investigations such as evidence of late gadolinium enhancement on magnetic resonance imaging, but may also have an important prognostic value once a definite diagnosis has been made. In addition, the presence of electrical stimulus conduction disturbances or advanced atrioventricular blocks that can be seen especially in conditions such as cardiac amyloidosis or sarcoidosis, or the presence of left bundle branch block or posterior fascicular block in dilated or arrhythmogenic left ventricular cardiomyopathies are recognized as a possible expression of advanced pathology. Similarly, the presence of ventricular arrhythmias with typical patterns such as non-sustained or sustained ventricular tachycardia of LBBB morphology in ARVC or non-sustained or sustained ventricular tachycardia with an RBBB morphology (excluding the "fascicular pattern") in arrhythmogenic left ventricle cardiomyopathy could have a significant impact on the course of each disease. It is therefore clear that a learned and careful interpretation of ECG features can raise suspicion of the presence of a cardiomyopathy, identify diagnostic "red flags" useful for orienting the diagnosis toward specific forms, and provide useful tools for risk stratification. The purpose of this review is to emphasize the important role of the ECG in the diagnostic workup, describing the main ECG findings of different cardiomyopathies.

T-Wave Analysis on the 24 h Holter ECG Monitoring as a Predictive Assessment of Major Adverse Cardiovascular Events in Patients with Myocardial Infarction: A Literature Review and Future Perspectives

Myocardial ischemia is a pathophysiological state characterized by inadequate perfusion of the myocardium, resulting in an imbalance between myocardial oxygen demand and supply. It is most commonly caused by coronary artery disease, in which atherosclerotic plaques lead to luminal narrowing and reduced blood flow to the heart. Myocardial ischemia can manifest as angina pectoris or silent myocardial ischemia and can progress to myocardial infarction or heart failure if left untreated. Diagnosis of myocardial ischemia typically involves a combination of clinical evaluation, electrocardiography and imaging studies. Electrocardiographic parameters, as assessed by 24 h Holter ECG monitoring, can predict the occurrence of major adverse cardiovascular events in patients with myocardial ischemia, independent of other risk factors. The T-waves in patients with myocardial ischemia have prognostic value for predicting major adverse cardiovascular events, and their electrophysiological heterogeneity can be visualized using various techniques. Combining the electrocardiographic findings with the assessment of myocardial substrate may offer a better picture of the factors that can contribute to cardiovascular death.

The electrocardiogram in non-ischaemic-dilated cardiomyopathy

This article summarizes the main electrocardiogram (ECG) findings in dilated cardiomyopathy (DCM) patients. Recent reports are described in the great 'pot' of DCM peculiar ECG patterns that are typical of specific forms of DCM. Patients with late gadolinium enhancement on CMR, who are at greatest arrhythmic risk, have also distinctive ECG features. Future studies in large DCM populations should evaluate the diagnostic and prognostic value of the ECG.

Pragmatic electrocardiogram tracings in non-ischaemic dilated cardiomyopathy: diagnostic and prognostic role

Dilated cardiomyopathy (DCM) is a primitive heart muscle disease characterized by a great heterogeneous aetiology and prognostic outcome. Dilated cardiomyopathy is an umbrella term encompassing different aetiologies that might require specific treatments. It principally affects young and male adults, with high-risk arrhythmic competitive risk. Unfortunately, the prevention of major ventricular arrhythmic events remains a clinical challenge. In the era of advanced multimodality imaging and widely available genetic testing, electrocardiogram (ECG) continues to represent a reliable diagnostic tool, for specific work up of every single patient. However, approaching DCM patients, only a cardiomyopathy-oriented reading makes the role of ECG central in the management of DCM, both for diagnosis, prognosis, and therapeutic management. In this paper, we present four ECGs of four different DCM patients, in order to guide a cardiomyopathy-oriented ECG reading, emphasizing its impact in an early, cost-effective, and personalized diagnostic and prognostic work up in this specific setting.

The value of the 12-lead electrocardiogram in the prediction of sudden cardiac death

Sudden cardiac death (SCD) can be caused by several clinical conditions, overt or misconceived, which recognize different pathophysiologies determining the development of fatal arrhythmic events. In the various forms of structural heart disease such as ischaemic heart disease, cardiomyopathies (e.g. hypertrophic cardiomyopathy, dilated cardiomyopathy, and arrhythmogenic cardiomyopathy), channelopathies (e.g. long-QT syndrome, congenital short QT, Brugada syndrome, early repolarization (ER) syndrome, and idiopathic ventricular fibrillation) but also in the apparently healthy subject, the 12-lead electrocardiogram (ECG) has proved, over the years, to be a reliable and readily available method for stratifying the risk of adverse arrhythmic events and consequently SCD. Several electrocardiographic markers have been shown to be associated with adverse outcomes in different types of patients. Although with different sensitivity and specificity in each clinical condition, depolarization abnormalities, such as QRS fragmentation, Q waves, QRS duration, left posterior fascicular block, low QRS voltage, and left ventricular hypertrophy and similarly repolarization abnormalities as ER pattern, T wave alternans, QT interval, and QT dispersion, have shown significant efficacy in predicting SCD. Despite the advancement of techniques especially in the field of imaging, the correct interpretation of the 12-lead ECG remains, therefore, an effective tool for assessing the possible prognostic outcome in terms of arrhythmic risk and SCD in different types of patients.

Simple screening model based on electrocardiogram for patients with dilated cardiomyopathy

Dilated cardiomyopathy (DCM) is one of the most common causes of heart failure. Therefore, screening and early diagnosis of potential DCM patients is beneficial. Electrocardiogram (ECG) can be an inexpensive and easily available screening tool. We aimed to construct a simple screening model for DCM based on electrocardiogram. In this retrospective observational study, we consecutively enrolled 117 DCM patients between July 1, 2016 and July 1, 2021 as the DCM group, while 117 patients hospitalized in the same period with normal echocardiography and ECG were selected as the non-DCM group. Patients were randomly assigned to the training and validation sets at 8:2. ECG parameters of left ventricular related leads were exacted. Logistic regression was performed to evaluate screening indicators of ECG parameters and a nomogram was conducted. The screening ability of the model was evaluated using receiver operating characteristic analysis. Furthermore, the nomogram was assessed using calibration curve and decision curve analysis. Screening indicators included in the nomogram were the amplitude of S wave in V1 and V3 leads, the amplitude of R wave in aVF and V6 leads, and PR interval. The nomogram performed satisfactory discrimination in the training (area under the receiver operating characteristic curve = 0.904) and validation (area under the receiver operating characteristic curve = 0.878) sets and good calibration (Hosmer-Lemeshow P = .066). Decision curve analysis demonstrated the model can generate a net benefit of 0.33 when the threshold probability was 0.543. The nomogram based on electrocardiogram is a simple and practical screening tool for potential DCM patients.

Electrocardiographic features of children with Duchenne muscular dystrophy

Duchenne muscular dystrophy (DMD) is a clinically common X-linked recessive myopathy, which is caused by mutation of the gene encoding dystrophin on chromosome Xp21. The onset of heart injury in children with DMD is inconspicuous, and the prognosis is poor once it develops to the stage of heart failure. Cardiovascular complications remain an important cause of death in this patient population. At present, population and animal studies have suggested that Electrocardiogram (ECG) changes may be the initial manifestation of cardiac involvement in children with DMD. Relevant clinical studies have also confirmed that significant abnormal ECG changes already exist in DMD patients before cardiomegaly and/or LVEF decrease. With increases in age and decreases in cardiac function, the proportion of ECG abnormalities in DMD patients increase significantly. Some characteristic ECG changes, such as ST-segment changes, T wave inversion, Q wave at the inferolateral leads, LBBB and SDANN, have a certain correlation with the indexes of cardiac remodeling or impaired cardiac function in DMD patients, while VT and LBBB have demonstrated relatively good predictive value for the occurrence of long-term DCM and/or adverse cardiovascular events or even death in DMD patients. The present review discusses the electrocardiographic features in children with DMD.

Arrhythmogenic Cardiomyopathy: Exercise Pitfalls, Role of Connexin-43, and Moving beyond Antiarrhythmics

Arrhythmogenic Cardiomyopathy (ACM), a Mendelian disorder that can affect both left and right ventricles, is most often associated with pathogenic desmosomal variants that can lead to fibrofatty replacement of the myocardium, a pathological hallmark of this disease. Current therapies are aimed to prevent the worsening of disease phenotypes and sudden cardiac death (SCD). Despite the use of implantable cardioverter defibrillators (ICDs) there is no present therapy that would mitigate the loss in electrical signal and propagation by these fibrofatty barriers. Recent studies have shown the influence of forced vs. voluntary exercise in a variety of healthy and diseased mice; more specifically, that exercised mice show increased Connexin-43 (Cx43) expression levels. Fascinatingly, increased Cx43 expression ameliorated the abnormal electrical signal conduction in the myocardium of diseased mice. These findings point to a major translational pitfall in current therapeutics for ACM patients, who are advised to completely cease exercising and already demonstrate reduced Cx43 levels at the myocyte intercalated disc. Considering cardiac dysfunction in ACM arises from the loss of cardiomyocytes and electrical signal conduction abnormalities, an increase in Cx43 expression-promoted by low to moderate intensity exercise and/or gene therapy-could very well improve cardiac function in ACM patients.

Dilated cardiomyopathy in the era of precision medicine: latest concepts and developments

Dilated cardiomyopathy (DCM) is an umbrella term entailing a wide variety of genetic and non-genetic etiologies, leading to left ventricular systolic dysfunction and dilatation, not explained by abnormal loading conditions or coronary artery disease. The clinical presentation can vary from asymptomatic to heart failure symptoms or sudden cardiac death (SCD) even in previously asymptomatic individuals. In the last 2 decades, there has been striking progress in the understanding of the complex genetic basis of DCM, with the discovery of additional genes and genotype-phenotype correlation studies. Rigorous clinical work-up of DCM patients, meticulous family screening, and the implementation of advanced imaging techniques pave the way for a more efficient and earlier diagnosis as well as more precise indications for implantable cardioverter defibrillator implantation and prevention of SCD. In the era of precision medicine, genotype-directed therapies have started to emerge. In this review, we focus on updates of the genetic background of DCM, characteristic phenotypes caused by recently described pathogenic variants, specific indications for prevention of SCD in those individuals and genotype-directed treatments under development. Finally, the latest developments in distinguishing athletic heart syndrome from subclinical DCM are described.

Artificial Intelligence-Enabled Electrocardiogram Predicted Left Ventricle Diameter as an Independent Risk Factor of Long-Term Cardiovascular Outcome in Patients With Normal Ejection Fraction

Background

Heart failure (HF) is a global disease with increasing prevalence in an aging society. However, the survival rate is poor despite the patient receiving standard treatment. Early identification of patients with a high risk of HF is important but challenging. Left ventricular end-diastolic diameter (LV-D) increase was an independent risk factor of HF and adverse cardiovascular (CV) outcomes. In this study, we aimed to develop an artificial intelligence (AI) enabled electrocardiogram (ECG) system to detect LV-D increase early.

Objective

We developed a deep learning model (DLM) to predict left ventricular end-diastolic and end-systolic diameter (LV-D and LV-S) with internal and external validations and investigated the relationship between ECG-LV-D and echocardiographic LV-D and explored the contributions of ECG-LV-D on future CV outcomes.

Methods

Electrocardiograms and corresponding echocardiography data within 7 days were collected and paired for DLM training with 99,692 ECGs in the development set and 20,197 ECGs in the tuning set. The other 7,551 and 11,644 ECGs were collected from two different hospitals to validate the DLM performance in internal and external validation sets. We analyzed the association and prediction ability of ECG-LVD for CV outcomes, including left ventricular (LV) dysfunction, CV mortality, acute myocardial infarction (AMI), and coronary artery disease (CAD).

Results

The mean absolute errors (MAE) of ECG-LV-D were 5.25/5.29, and the area under the receiver operating characteristic (ROC) curves (AUCs) were 0.8297/0.8072 and 0.9295/0.9148 for the detection of mild (56 ≦ LV-D < 65 mm) and severe (LV-D ≧ 65 mm) LV-D dilation in internal/external validation sets, respectively. Patients with normal ejection fraction (EF) who were identified as high ECHO-LV-D had the higher hazard ratios (HRs) of developing new onset LV dysfunction [HR: 2.34, 95% conference interval (CI): 1.78–3.08], CV mortality (HR 2.30, 95% CI 1.05–5.05), new-onset AMI (HR 2.12, 95% CI 1.36–3.29), and CAD (HR 1.59, 95% CI 1.26–2.00) in the internal validation set. In addition, the ECG-LV-D presents a 1.88-fold risk (95% CI 1.47–2.39) on new-onset LV dysfunction in the external validation set.

Conclusion

The ECG-LV-D not only identifies high-risk patients with normal EF but also serves as an independent risk factor of long-term CV outcomes.

Predictive value of electrocardiographic markers in children with dilated cardiomyopathy

Dilated cardiomyopathy (DCM) refers to a heterogeneous group of cardiomyopathies characterized by ventricular dilatation and myocardial systolic dysfunction, which can lead to serious consequences such as malign arrhythmia, sudden death, heart failure, and thromboembolism. With its economical, non-invasive, simple and reproducible advantages, electrocardiogram (ECG) has become an important indicator for assessing the prognosis of cardiovascular diseases. In recent years, more and more studies of electrocardiography on DCM have been carried out, but there is still a lack of a comprehensive summary of its prognostic value. This article reviews the prognostic value of electrocardiographic markers in children with DCM.

Contemporary etiology and prognosis of dilated non-ischemic cardiomyopathy

INTRODUCTION

Non-ischemic dilated cardiomyopathy (NI-DCM) represents a specific etiology of systolic heart failure that usually affect young individuals with a genetic background in up to 40% of cases. Behind the term NI-DCM there is a spectrum of different diseases, and an accurate etiological classification appears pivotal for the clinical management and prognostic stratification of these patients.

EVIDENCE ACQUISITION

In the last years the prognosis of NI-DCM patients dramatically improved thanks to the progresses in medical treatment/ device therapy and earlier diagnosis especially in familial context. In this review we summarize the actual state of art in the management of these patients.

EVIDENCE SYNTHESIS

In the era of precision medicine, a lot of progresses have been made to expand our knowledge on the management of NI-DCM patients. A complex interaction between genotype and external triggers is the main determinant of the clinical phenotype in NI-DCM, and a lot of efforts must be done by clinicians to systematically rule out all the possible causes involved in the pathogenesis. Progresses in cardiac imaging and familial screening led us to detect subtle abnormalities in the initial phase of the disease and also helped us to furtherly stratify the prognosis and arrhythmic risk of these patients. It is plausible that a more precise etiological classification will be needed in the near future.

CONCLUSIONS

NI-DCM contains a spectrum of different diseases. Proper etiological classification, early diagnosis and strict follow-up are essential to tailor care of these patients.

Association of T-wave abnormalities with major cardiovascular events in diabetes: the ACCORD trial

AIMS/HYPOTHESIS

T-wave abnormalities (TWA) are often found on ECG and signify abnormal ventricular repolarisation. While TWA have been shown to be associated with subclinical atherosclerosis, the relationship between TWA and hard cardiovascular endpoints is less clear and may differ in the presence of diabetes, so we sought to explore these associations in participants from the Action to Control Cardiovascular Risk in Diabetes (ACCORD) trial.

METHODS

TWA were operationally defined as the presence of any Minnesota Codes 5-1 through 5-4 in any lead distribution. Multivariable Cox proportional hazards models were constructed to examine relationships between TWA and clinical cardiovascular events. Secondary analyses explored the risks conferred by major vs minor TWA, differential effects of TWA by anatomic localisation (anterolateral, inferior or anterior lead distributions), and differing associations in those with or without prevalent CVD.

RESULTS

Among 8176 eligible participants (mean 62.1 ± 6.3 SD years, 61.4% male), there were 3759 cardiovascular events, including 1430 deaths (473 of a cardiovascular aetiology), 474 heart failure events, 1452 major CHD events and 403 strokes. Participants with TWA had increased risks of all-cause mortality (HR 1.45 [95% CI 1.30, 1.62], p < 0.0001), cardiovascular mortality (HR 1.93 [1.59, 2.34], p = 0.0001), congestive heart failure (HR 2.04 [1.69, 2.48], p < 0.0001) and major CHD (HR 1.40 [1.26, 1.57], p < 0.0001), but no increased risk of stroke (HR 0.99 [0.80, 1.23], p = 0.95). Major TWA conferred a higher risk than minor TWA. When TWA were added to the UK Prospective Diabetes Study risk engine, there was improved discrimination for incident CHD events, but only for those with prevalent CVD (area under the receiver operating characteristic curve 0.5744 and 0.6030 with p = 0.0067). Adding TWA to the risk engine yielded improvements in reclassification that were of greater magnitude in those with prevalent CVD (net reclassification improvement [NRI] 0.24 [95% CI 0.16, 0.32] in those with prevalent CVD, NRI 0.14 [95% CI 0.07, 0.22] in those without prevalent CVD).

CONCLUSIONS/INTERPRETATION

The presence and magnitude of TWA are associated with increased risk of clinical cardiovascular events and mortality in individuals with diabetes and may have value in refining risk, particularly in those with prevalent CVD. Graphical abstract.

Clinical significance of ischemia-like electrocardiographic finding during heart failure treatment on left ventricular recovery in patients with non-ischemic dilated cardiomyopathy

BACKGROUND

Patients with non-ischemic dilated cardiomyopathy (DCM) often show ischemia-like electrocardiographic findings. We aimed to elucidate the clinical impact of ischemia-like electrocardiographic findings in DCM, focusing on left ventricular reverse remodeling (LVRR).

METHODS

We evaluated 195 patients hospitalized with heart failure (HF) and diagnosed with DCM. All patients underwent twelve-lead electrocardiography (ECG) and echocardiography during hospitalization and at the 2-year follow-up.

RESULTS

During hospitalization, 152 (78%) patients experienced ischemia-like ECG findings (Minnesota codes I3, IV1-3, V1-3, or VII1); 43 patients (22%, non-ischemia-like group) did not experience these findings. Ischemia-like ECG findings were normalized during hospitalization in 64 patients (33%, transient-ischemia-like group) but were unchanged in 88 patients (45%, persistent-ischemia-like group). The highest rates of LVRR, defined as an increase in LV ejection fraction from ≥10% to a final value of ≥35%, along with decreased LV end-diastolic dimension of ≥10% during 2 years of follow-up, were shown in the transient-ischemia-like group (transient-ischemia-like group, 91%; persistent-ischemia-like group, 40%; non-ischemia-like-group, 51%; p < 0.001). The transient-ischemia-like group had lowest composite event rates, including readmission for HF, the detection of major ventricular arrhythmia, and sudden cardiac death.

CONCLUSIONS

Normalization of ischemia-like ECG findings during the first HF treatments was associated with a higher occurrence of mid-term LVRR and favorable long-term outcome in patients with DCM.

Apparent electrocardiogram left ventricular hypertrophy during tachycardia

The electrocardiographic transient display of left ventricular hypertrophy (LVH), during rapid heart rates, in the setting of sinus/supraventricular tachycardias and atrial fibrillation, is illustrated via 3 case reports. This common occurrence is expressed by an increase in the S-waves in leads V2-V5, during tachycardias, rendering a false positive diagnosis of LVH by the frequently employed Cornell voltage LVH criteria. This tachycardia-mediated apparent LVH, is unrelated to the occasionally encountered stable, and unrelated to tachycardia, "false positive diagnosis of LVH", which could in reality occasionally reflect altered electrical properties of myocardium that could create a functional substrate for developing arrhythmias. The importance of awareness of this insight by all health professionals is immeasurable, considering that a false positive diagnosis of LVH has major consequences in the management, prognostication, resort to expensive unnecessary testing, and stress to the patients and their families.

Diagnostic and prognostic value of low QRS voltages in cardiomyopathies: old but gold

The interpretation of 12-lead resting electrocardiogram (ECG) in patients with a definitive diagnosis or with the suspicion of a cardiomyopathy represents a cornerstone for the diagnostic work up and management of patients. Although low electrocardiographic QRS voltages (LQRSV) detected by 12-lead resting ECG have historically been acknowledged by physicians, in view of recent evidence on the demonstration of myocardial scar by cardiac magnetic resonance and its relevance as a cause of sudden cardiac death even in young individuals, a new interest has been raised about the utility of LQRSV in the clinical practice. Beyond their diagnostic value, LQRSV have also demonstrated a prognostic role in different cardiomyopathies. The present review summarizes the diagnostic and prognostic value of LQRSV in cardiomyopathies, reporting the new evidence, primarily based on advanced imaging studies, supporting the clinical utility of this parameter.

Management of nonischemic-dilated cardiomyopathies in clinical practice: a position paper of the working group on myocardial and pericardial diseases of Italian Society of Cardiology

: Nonischemic-dilated cardiomyopathy (NIDCM) is an entity that gathers extremely heterogeneous diseases. This awareness, although leading to continuous improvement in survival, has increased the complexity of NIDCM patients' management. Even though the endorsed 'red-flags' approach helps clinicians in pursuing an accurate etiological definition in clinical practice, it is not clear when and how peripheral centers should interact with referral centers with specific expertise in challenging scenarios (e.g. postmyocarditis and genetically determined dilated cardiomyopathy) and with easier access to second-line diagnostic tools and therapies. This position paper will summarize each step in NIDCM management, highlighting the multiple interactions between peripheral and referral centers, from first-line diagnostic workup and therapy to advanced heart failure management and long-term follow-up.